<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style type="text/css">
        #jack{
            width: 100px;
            height: 100px;
            background:rgba(234, 0, 255, 0.459);

        }
        @keyframes donghua{
            from{
                background-color:rgba(234, 0, 255, 0.459);
            }
            50%{
                background-color: aqua;
            }
            75%{
                background-color: azure;
            }
            100%{
                background-color: aquamarine;
            }
        }
    </style>
</head>
<body>
    <div id="jack"></div>
</body>
</html>